/*
 * Bittorrent Client using Qt4 and libtorrent.
 * Copyright (C) 2006-2012  Christophe Dumez
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
 *
 * In addition, as a special exception, the copyright holders give permission to
 * link this program with the OpenSSL project's "OpenSSL" library (or with
 * modified versions of it that use the same license as the "OpenSSL" library),
 * and distribute the linked executables. You must obey the GNU General Public
 * License in all respects for all of the code used other than "OpenSSL".  If you
 * modify file(s), you may extend this exception to your version of the file(s),
 * but you are not obligated to do so. If you do not wish to do so, delete this
 * exception statement from your version.
 *
 * Contact : chris@qbittorrent.org
 */

#include <QDir>
#include <QIcon>

#include "guiiconprovider.h"
#include "base/utils/misc.h"
#include "base/utils/fs.h"
#include "torrentcontentmodel.h"
#include "torrentcontentmodelitem.h"
#include "torrentcontentmodelfolder.h"
#include "torrentcontentmodelfile.h"

namespace
{
    QIcon getDirectoryIcon()
    {
        static QIcon cached = GuiIconProvider::instance()->getIcon("inode-directory");
        return cached;
    }

    QIcon getFileIcon()
    {
        static QIcon cached = GuiIconProvider::instance()->getIcon("text-plain");
        return cached;
    }
}

TorrentContentModel::TorrentContentModel(QObject *parent)
    : QAbstractItemModel(parent)
    , m_rootItem(new TorrentContentModelFolder(QList<QVariant>({ tr("Name"), tr("Size"), tr("Progress"), tr("Download Priority"), tr("Remaining") })))
{
}

TorrentContentModel::~TorrentContentModel()
{
    delete m_rootItem;
}

void TorrentContentModel::updateFilesProgress(const QVector<qreal> &fp)
{
    Q_ASSERT(m_filesIndex.size() == fp.size());
    // XXX: Why is this necessary?
    if (m_filesIndex.size() != fp.size()) return;

    emit layoutAboutToBeChanged();
    for (int i = 0; i < fp.size(); ++i)
        m_filesIndex[i]->setProgress(fp[i]);
    // Update folders progress in the tree
    m_rootItem->recalculateProgress();
    emit dataChanged(index(0, 0), index(rowCount(), columnCount()));
}

void TorrentContentModel::updateFilesPriorities(const QVector<int> &fprio)
{
    Q_ASSERT(m_filesIndex.size() == (int)fprio.size());
    // XXX: Why is this necessary?
    if (m_filesIndex.size() != (int)fprio.size())
        return;

    emit layoutAboutToBeChanged();
    for (int i = 0; i < fprio.size(); ++i)
        m_filesIndex[i]->setPriority(fprio[i]);
    emit dataChanged(index(0, 0), index(rowCount(), columnCount()));
}

QVector<int> TorrentContentModel::getFilePriorities() const
{
    QVector<int> prio;
    prio.reserve(m_filesIndex.size());
    foreach (const TorrentContentModelFile* file, m_filesIndex)
        prio.push_back(file->priority());
    return prio;
}

bool TorrentContentModel::allFiltered() const
{
    foreach (const TorrentContentModelFile* fileItem, m_filesIndex)
        if (fileItem->priority() != prio::IGNORED)
            return false;
    return true;
}

int TorrentContentModel::columnCount(const QModelIndex& parent) const
{
    if (parent.isValid())
        return static_cast<TorrentContentModelItem*>(parent.internalPointer())->columnCount();
    else
        return m_rootItem->columnCount();
}

bool TorrentContentModel::setData(const QModelIndex& index, const QVariant& value, int role)
{
    if (!index.isValid())
        return false;

    if ((index.column() == 0) && (role == Qt::CheckStateRole)) {
        TorrentContentModelItem *item = static_cast<TorrentContentModelItem*>(index.internalPointer());
        qDebug("setData(%s, %d", qPrintable(item->name()), value.toInt());
        if (item->priority() != value.toInt()) {
            if (value.toInt() == Qt::PartiallyChecked)
                item->setPriority(prio::MIXED);
            else if (value.toInt() == Qt::Unchecked)
                item->setPriority(prio::IGNORED);
            else
                item->setPriority(prio::NORMAL);
            // Update folders progress in the tree
            m_rootItem->recalculateProgress();
            emit dataChanged(this->index(0, 0), this->index(rowCount() - 1, columnCount() - 1));
            emit filteredFilesChanged();
        }
        return true;
    }

    if (role == Qt::EditRole) {
        Q_ASSERT(index.isValid());
        TorrentContentModelItem* item = static_cast<TorrentContentModelItem*>(index.internalPointer());
        switch (index.column()) {
        case TorrentContentModelItem::COL_NAME:
            item->setName(value.toString());
            break;
        case TorrentContentModelItem::COL_PRIO:
            item->setPriority(value.toInt());
            break;
        default:
            return false;
        }
        emit dataChanged(index, index);
        return true;
    }

    return false;
}

TorrentContentModelItem::ItemType TorrentContentModel::itemType(const QModelIndex& index) const
{
    return static_cast<const TorrentContentModelItem*>(index.internalPointer())->itemType();
}

int TorrentContentModel::getFileIndex(const QModelIndex& index)
{
    TorrentContentModelItem *item = static_cast<TorrentContentModelItem*>(index.internalPointer());
    if (item->itemType() == TorrentContentModelItem::FileType)
        return static_cast<TorrentContentModelFile*>(item)->fileIndex();

    Q_ASSERT(item->itemType() == TorrentContentModelItem::FileType);
    return -1;
}

QVariant TorrentContentModel::data(const QModelIndex& index, int role) const
{
    if (!index.isValid())
        return QVariant();

    TorrentContentModelItem* item = static_cast<TorrentContentModelItem*>(index.internalPointer());
    if ((index.column() == 0) && (role == Qt::DecorationRole)) {
        if (item->itemType() == TorrentContentModelItem::FolderType)
            return getDirectoryIcon();
        else
            return getFileIcon();
    }
    if ((index.column() == 0) && (role == Qt::CheckStateRole)) {
        if (item->data(TorrentContentModelItem::COL_PRIO).toInt() == prio::IGNORED)
            return Qt::Unchecked;
        if (item->data(TorrentContentModelItem::COL_PRIO).toInt() == prio::MIXED)
            return Qt::PartiallyChecked;
        return Qt::Checked;
    }
    if (role != Qt::DisplayRole)
        return QVariant();

    return item->data(index.column());
}

Qt::ItemFlags TorrentContentModel::flags(const QModelIndex& index) const
{
    if (!index.isValid())
        return 0;

    if (itemType(index) == TorrentContentModelItem::FolderType)
        return Qt::ItemIsEditable | Qt::ItemIsEnabled | Qt::ItemIsSelectable | Qt::ItemIsUserCheckable | Qt::ItemIsTristate;

    return Qt::ItemIsEditable | Qt::ItemIsEnabled | Qt::ItemIsSelectable | Qt::ItemIsUserCheckable;
}

QVariant TorrentContentModel::headerData(int section, Qt::Orientation orientation, int role) const
{
    if ((orientation == Qt::Horizontal) && (role == Qt::DisplayRole))
        return m_rootItem->data(section);

    return QVariant();
}

QModelIndex TorrentContentModel::index(int row, int column, const QModelIndex& parent) const
{
    if (parent.isValid() && (parent.column() != 0))
        return QModelIndex();

    if (column >= TorrentContentModelItem::NB_COL)
        return QModelIndex();

    TorrentContentModelFolder* parentItem;
    if (!parent.isValid())
        parentItem = m_rootItem;
    else
        parentItem = static_cast<TorrentContentModelFolder*>(parent.internalPointer());
    Q_ASSERT(parentItem);

    if (row >= parentItem->childCount())
        return QModelIndex();

    TorrentContentModelItem* childItem = parentItem->child(row);
    if (childItem)
        return createIndex(row, column, childItem);
    return QModelIndex();
}

QModelIndex TorrentContentModel::parent(const QModelIndex& index) const
{
    if (!index.isValid())
        return QModelIndex();

    TorrentContentModelItem* childItem = static_cast<TorrentContentModelItem*>(index.internalPointer());
    if (!childItem)
        return QModelIndex();

    TorrentContentModelItem *parentItem = childItem->parent();
    if (parentItem == m_rootItem)
        return QModelIndex();

    return createIndex(parentItem->row(), 0, parentItem);
}

int TorrentContentModel::rowCount(const QModelIndex& parent) const
{
    if (parent.column() > 0)
        return 0;

    TorrentContentModelFolder* parentItem;
    if (!parent.isValid())
        parentItem = m_rootItem;
    else
        parentItem = dynamic_cast<TorrentContentModelFolder*>(static_cast<TorrentContentModelItem*>(parent.internalPointer()));

    return parentItem ? parentItem->childCount() : 0;
}

void TorrentContentModel::clear()
{
    qDebug("clear called");
    beginResetModel();
    m_filesIndex.clear();
    m_rootItem->deleteAllChildren();
    endResetModel();
}

void TorrentContentModel::setupModelData(const BitTorrent::TorrentInfo &info)
{
    qDebug("setup model data called");
    if (info.filesCount() == 0)
        return;

    emit layoutAboutToBeChanged();
    // Initialize files_index array
    qDebug("Torrent contains %d files", info.filesCount());
    m_filesIndex.reserve(info.filesCount());

    TorrentContentModelFolder* currentParent;
    // Iterate over files
    for (int i = 0; i < info.filesCount(); ++i) {
        currentParent = m_rootItem;
        QString path = Utils::Fs::fromNativePath(info.filePath(i));
        // Iterate of parts of the path to create necessary folders
        QStringList pathFolders = path.split("/", QString::SkipEmptyParts);
        pathFolders.removeLast();
        foreach (const QString& pathPart, pathFolders) {
            if (pathPart == ".unwanted")
                continue;
            TorrentContentModelFolder* newParent = currentParent->childFolderWithName(pathPart);
            if (!newParent) {
                newParent = new TorrentContentModelFolder(pathPart, currentParent);
                currentParent->appendChild(newParent);
            }
            currentParent = newParent;
        }
        // Actually create the file
        TorrentContentModelFile* fileItem = new TorrentContentModelFile(info.fileName(i), info.fileSize(i), currentParent, i);
        currentParent->appendChild(fileItem);
        m_filesIndex.push_back(fileItem);
    }
    emit layoutChanged();
}

void TorrentContentModel::selectAll()
{
    for (int i = 0; i < m_rootItem->childCount(); ++i) {
        TorrentContentModelItem* child = m_rootItem->child(i);
        if (child->priority() == prio::IGNORED)
            child->setPriority(prio::NORMAL);
    }
    emit dataChanged(index(0, 0), index(rowCount(), columnCount()));
}

void TorrentContentModel::selectNone()
{
    for (int i = 0; i < m_rootItem->childCount(); ++i)
        m_rootItem->child(i)->setPriority(prio::IGNORED);
    emit dataChanged(index(0, 0), index(rowCount(), columnCount()));
}
